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Batch encrypt existing ZIP files #

zipcloak encrypts all unencrypted entries in a ZIP file, but it does not support wildcards in filenames (e.g., *.zip) for batch processing, nor does it allow passing the password in an argument; one must enter and reenter the password manually:
C:\>zipcloak.exe foo.zip
Enter password:
Verify password:
encrypting: baz.txt
encrypting: bar.txt
or jury-rig something like expect.

Happily, T. Furukawa crafted a patch for zipcloak that adds a password option, so batch processing is much easier:
C:\>for %f in (*.zip) do zipcloak -p password %f
Download the patch and/or binary from the above link or this local cache.

Batch password-protecting existing ZIP files can also be done with WinRAR (Select ZIP files > Tools > Convert archives > Compression... > Set password...) or PeaZip (Select ZIP files > Convert > Enter password / keyfile (optionally set algorithm to ZipCrypto under the Advanced tab for compatibility with Windows' built-in ZIP handling)). Note that filenames within ZIP archives are not encrypted; see Filenames display without entering the password when an encrypted Zip file is opened for more information and a workaround. Further note that the encryption algorithm used by zipcloak and ZipCrypto is very weak.

/windows | Nov 22, 2014

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